Writing Hours Tracker

[dG9hc3Q]

Summary

A Writing Hours Tracker — passively measure time spent actually writing
(per project, per day) and surface it, JetBrains "time tracking" style.
Distinct from the existing per-document writing stats (src/editor/stat.rs,
word/line/syllable counts) — this is time, not text.

Motivation

The end goal is a serious tool for working poets; "how many hours did I put
in this week" is a core habit metric. Fully local, no account.

Scope (v1)

• Count a minute as "active" when there was a keystroke / edit in the last
  N seconds and the window is focused; idle time is not counted.
• Aggregate per calendar day and per workspace/project.
• Persist to a local file under the OS data dir (same location convention as
  Settings), plain and human-readable.
• A small status-bar segment (today's total) + a panel or dialog with a
  day / week / month breakdown and a simple bar chart.

Offline-first / privacy (non-negotiable #4, #5)

• 100% local. No telemetry, no phone-home, no analytics — the data never
  leaves the machine. An off switch in Settings; a "clear history" action.

Files (sketch)

• new src/tools/hours.rs — the timer, idle detection, aggregation, store.
• hook editor buffer changed + window focus events to feed it.
• status-bar segment in app/layout.rs; optional panel/dialog.
• track_writing_hours setting via the existing settings pattern.